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991.
A 53-year-old man presented with a rare meningioma associated with Werner syndrome. Screening brain magnetic resonance (MR) imaging with gadolinium had detected multiple homogeneously enhanced tumors in the right convexity and in the anterior and posterior thirds of the falx cerebri after surgery for osteosarcoma in his right leg at age 52 years. Ten months later, the right convexity tumor was removed because follow-up MR imaging detected tumor growth. The histological diagnosis was transitional meningioma. The postoperative clinical course was good and the patient remains healthy. Review of the literature found meningiomas associated with Werner syndrome occur about two times more frequently in men than in women, and typically in the fourth decade. Most meningiomas associated with Werner syndrome are benign, but are sometimes complicated with extracranial tumors such as sarcoma, thyroid carcinoma, and others. Patients with meningioma associated with Werner syndrome should be carefully followed up to detect the occurrence of other extracranial tumors such as sarcoma by brain MR imaging, echography, or body computed tomography.  相似文献   
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995.
Several cell types isolated from adult tissues have been reported to differentiate into mature kidney cells that may participate in renal repair after systemic administration. Chen et al. report that local mesenchymal stem cells derived from adult mouse kidneys are another source of cells with similar properties. Although these cells have the potential to differentiate into endothelial-lineage cell types, their therapeutic benefit to the ischemic kidney is mainly via the production of renoprotective factors.  相似文献   
996.
The objective of this study was to evaluate in vivo kinematics of a high-flexion, posterior-stabilized fixed-bearing, total knee arthroplasty in weight-bearing deep knee-bending motion. A total of 20 knees implanted with the Scorpio Non-Restrictive Geometry knee system in 17 patients were assessed in this study. The Scorpio Non-Restrictive Geometry is a recent implant design with modifications made to accommodate a higher flexion range of motion and greater axial rotation, particularly during more functionally demanding activities. Patients were examined during a deep knee-bending motion using fluoroscopy, and femorotibial motion was determined using a 2-dimensional to 3-dimensional registration technique. The average flexion angle was 126.5° (110°-149°). The femoral component demonstrated a mean of 13.5° (5.2°-21°) external rotation. The external rotation increased up to maximum flexion. The pivot pattern was a medial pivot pattern similar to that reported in normal knee kinematics.  相似文献   
997.
We report a rare case of simultaneous repair for Cor triatriatum (CT), partially unroofed coronary sinus (CS) with persistent left superior vena cava (PLSVC), moderately severe tricuspid regurgitation, and atrial flutter 35 years after radical operation for tetralogy of Fallot (TOF). A 40-year-old woman underwent patch closure of atrial septal defect as to drain blood from left SVC to right atrium (RA), excision of diaphragm in left atrium (LA), tricuspid annuloplasty, and cryoablation. Postoperative course was uneventful with successful anatomical correction.  相似文献   
998.
Diesel exhaust particles disturb gene expression in mouse testis   总被引:3,自引:0,他引:3  
Inhalation of diesel exhaust particles (DEP) has been found to reduce sperm production. There is a possibility that DEP exposure elicits changes in gene expression in testis. To identify the alteration of gene expression resulting from DEP exposure, we constructed subtracted cDNA libraries from mouse testis using the suppression subtractive hybridization method. We isolated 16 candidate clones whose expression levels changed after exposure. Some of these candidates were highly similar to known testis-specific genes. Some of the clones also seemed to correlate with spermatogenesis. Northern blot analysis revealed that DEP exposure changed the expression levels of several clones in a dose-dependent manner. For example, the expression of clone R8, which was very similar to human XRRA1, increased by 2.3-fold in testis after DEP exposure. On the other hand, the expressions of long-chain acyl-CoA synthetase 6 (Acsl6) and serine/threonine kinase 35 reduced by 0.3-fold. These results indicated that some constituents of DEP alter gene expression in the testis.  相似文献   
999.
We measured the concentrations of monoamines in the brain of Japanese medaka, Oryzias latipes, exposed to tributyltin (TBT). Fish were exposed to 0, 1, 5, 25, or 125 microg g(-1) of TBT via the diet for 21 days. After the administration period, six males and six females in each treatment group were dissected and their brains were collected. The following monoamines were analyzed: dopamine (DA), norepinephrine (NE), epinephrine (E), and 5-hydroxytryptamine (5-HT). The metabolites of DA, 3,4-dihydroxyphenylacetic acid and homovanilic acid, and the metabolite of 5-HT, 5-hydroxyindolacetic acid were also analyzed. The concentration of DA in the brain of male medaka and the concentrations of 5-HT and NE in the female brains were significantly decreased by exposure to 125 microg TBT g(-1). The concentrations of 5-HT and NE in males and of DA in females were slightly decreased by 125 micrg g(-1) of TBT, although the differences were not statistically significant. The present study demonstrates that TBT alters monoamine concentrations in the brain of medaka.  相似文献   
1000.
The role of multi-detector-row computed tomographic angiography (MDCTA) in spinal vascular malformations has not yet been determined. We present a report on a short series of spinal arteriovenous fistulae (AVF) evaluated by MDCTA. With 4-row and 16-row MDCTA, three cases of spinal dural AVF and one case of perimedullary AVF were examined. Each case was also examined by magnetic resonance (MR) imaging and spinal catheter angiography. In two patients with spinal dural AVF, including one patient with angiographically occult AVF, MDCTA successfully located the site of the AVF in a multi-planar reformation image. MDCTA failed to locate the remaining case of spinal dural AVF, probably due to the small amount of shunting blood volume at the fistula. In a patient with perimedullary AVF, MDCTA visualized the broad range of the lesion, including the anterior spinal artery as a single feeder, the fistulous point, and the single perimedullary draining vein. In conclusion, although conventional spinal angiography might be still essential, MDCTA provides useful information for the surgeon in treatment of the spinal dural AVF. Further accumulation of clinical cases is required to determine the potential of MDCTA for perimedullary AVF. MDCTA should be considered as a choice of investigation in the evaluation of spinal AVFs.  相似文献   
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